Commit 6195c67d authored by Kirill Smelkov's avatar Kirill Smelkov

X xnet moved -> go123

parent 9a692ffd
// Copyright (C) 2017 Nexedi SA and Contributors.
// Kirill Smelkov <kirr@nexedi.com>
//
// This program is free software: you can Use, Study, Modify and Redistribute
// it under the terms of the GNU General Public License version 3, or (at your
// option) any later version, as published by the Free Software Foundation.
//
// You can also Link and Combine this program with other software covered by
// the terms of any of the Free Software licenses or any of the Open Source
// Initiative approved licenses and Convey the resulting work. Corresponding
// source of such a combination shall include the source code for all other
// software used.
//
// This program is distributed WITHOUT ANY WARRANTY; without even the implied
// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
//
// See COPYING file for full licensing terms.
// See https://www.nexedi.com/licensing for rationale and options.
// Package xnet provides addons to std package net.
package xnet
import (
"context"
"net"
"crypto/tls"
)
// Networker is interface representing access-point to a streaming network
type Networker interface {
// Network returns name of the network
Network() string
// XXX +Addr() net.Addr -> address of this access-point on underlying network ?
// Dial connects to addr on underlying network
// see net.Dial for semantic details
Dial(ctx context.Context, addr string) (net.Conn, error)
// Listen starts listening on local address laddr on underlying network access-point
// see net.Listen for semantic details
//
// XXX also introduce xnet.Listener in which Accept() accepts also ctx?
Listen(laddr string) (net.Listener, error)
}
// NetPlain creates Networker corresponding to regular network accessors from std package net.
//
// network is "tcp", "tcp4", "tcp6", "unix", etc...
func NetPlain(network string) Networker {
return netPlain(network)
}
type netPlain string
func (n netPlain) Network() string {
return string(n)
}
func (n netPlain) Dial(ctx context.Context, addr string) (net.Conn, error) {
d := net.Dialer{}
return d.DialContext(ctx, string(n), addr)
}
func (n netPlain) Listen(laddr string) (net.Listener, error) {
return net.Listen(string(n), laddr)
}
// NetTLS wraps underlying networker with TLS layer according to config.
//
// The config must be valid:
// - for tls.Client -- for Dial to work,
// - for tls.Server -- for Listen to work.
func NetTLS(inner Networker, config *tls.Config) Networker {
return &netTLS{inner, config}
}
type netTLS struct {
inner Networker
config *tls.Config
}
func (n *netTLS) Network() string {
return n.inner.Network() + "+tls"
}
func (n *netTLS) Dial(ctx context.Context, addr string) (net.Conn, error) {
c, err := n.inner.Dial(ctx, addr)
if err != nil {
return nil, err
}
return tls.Client(c, n.config), nil
}
func (n *netTLS) Listen(laddr string) (net.Listener, error) {
l, err := n.inner.Listen(laddr)
if err != nil {
return nil, err
}
return tls.NewListener(l, n.config), nil
}
// Copyright (C) 2017 Nexedi SA and Contributors.
// Kirill Smelkov <kirr@nexedi.com>
//
// This program is free software: you can Use, Study, Modify and Redistribute
// it under the terms of the GNU General Public License version 3, or (at your
// option) any later version, as published by the Free Software Foundation.
//
// You can also Link and Combine this program with other software covered by
// the terms of any of the Free Software licenses or any of the Open Source
// Initiative approved licenses and Convey the resulting work. Corresponding
// source of such a combination shall include the source code for all other
// software used.
//
// This program is distributed WITHOUT ANY WARRANTY; without even the implied
// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
//
// See COPYING file for full licensing terms.
// See https://www.nexedi.com/licensing for rationale and options.
// Package pipenet provides TCP-like synchronous in-memory network of net.Pipes.
//
// Addresses on pipenet are host:port pairs. A host is xnet.Networker and so
// can be worked with similarly to regular TCP network with Dial/Listen/Accept/...
//
// Example:
//
// net := pipenet.New("")
// h1 := net.Host("abc")
// h2 := net.Host("def")
//
// l, err := h1.Listen(":10") // starts listening on address "abc:10"
// go func() {
// csrv, err := l.Accept() // csrv will have LocalAddr "abc:10"
// }()
// ccli, err := h2.Dial("abc:10") // ccli will have RemoteAddr "def:10"
//
// Pipenet might be handy for testing interaction of networked applications in 1
// process without going to OS networking stack.
package pipenet
import (
"context"
"errors"
"net"
"strconv"
"sync"
"lab.nexedi.com/kirr/neo/go/xcommon/xnet"
)
const NetPrefix = "pipe" // pipenet package creates only "pipe*" networks
var (
errNetClosed = errors.New("network connection closed")
errAddrAlreadyUsed = errors.New("address already in use")
errAddrNoListen = errors.New("cannot listen on requested address")
errConnRefused = errors.New("connection refused")
)
// Addr represents address of a pipenet endpoint
type Addr struct {
Net string // full network name, e.g. "pipe"
Host string // name of host access point on the network
Port int // port on host
}
// Network implements synchronous in-memory network of pipes
type Network struct {
// name of this network under "pipe" namespace -> e.g. ""
// full network name will be reported as "pipe"+name
name string
// big network lock for everything dynamic under Network
// (e.g. Host.socketv too)
mu sync.Mutex
hostMap map[string]*Host
}
// Host represents named access point on Network
type Host struct {
network *Network
name string
// NOTE protected by Network.mu
socketv []*socket // port -> listener | conn ; [0] is always nil
}
var _ xnet.Networker = (*Host)(nil)
// socket represents one endpoint entry on Network
// it can be either already connected or listening
type socket struct {
host *Host // host/port this socket is bound to
port int
conn *conn // connection endpoint is here if != nil
listener *listener // listener is waiting here if != nil
}
// conn represents one endpoint of connection created under Network
type conn struct {
socket *socket
peersk *socket // the other side of this connection
net.Conn
closeOnce sync.Once
}
// listener implements net.Listener for piped network
type listener struct {
// network/host/port we are listening on
socket *socket
dialq chan dialReq // Dial requests to our port go here
down chan struct{} // Close -> down=ready
closeOnce sync.Once
}
// dialReq represents one dial request to listener
type dialReq struct {
from *Host
resp chan net.Conn
}
// ----------------------------------------
// New creates new pipenet Network
//
// name is name of this network under "pipe" namespace, e.g. "α" will give full network name "pipeα".
//
// New does not check whether network name provided is unique.
func New(name string) *Network {
return &Network{name: name, hostMap: make(map[string]*Host)}
}
// Host returns network access point by name
//
// If there was no such host before it creates new one.
func (n *Network) Host(name string) *Host {
n.mu.Lock()
defer n.mu.Unlock()
host := n.hostMap[name]
if host == nil {
host = &Host{network: n, name: name}
n.hostMap[name] = host
}
return host
}
// resolveAddr resolves addr on the network from the host point of view
// must be called with Network.mu held
func (h *Host) resolveAddr(addr string) (host *Host, port int, err error) {
a, err := h.network.ParseAddr(addr)
if err != nil {
return nil, 0, err
}
// local host if host name omitted
if a.Host == "" {
a.Host = h.name
}
host = h.network.hostMap[a.Host]
if host == nil {
return nil, 0, &net.AddrError{Err: "no such host", Addr: addr}
}
return host, a.Port, nil
}
// Listen starts new listener
//
// It either allocates free port if laddr is "" or with 0 port, or binds to laddr.
// Once listener is started, Dials could connect to listening address.
// Connection requests created by Dials could be accepted via Accept.
func (h *Host) Listen(laddr string) (net.Listener, error) {
h.network.mu.Lock()
defer h.network.mu.Unlock()
var sk *socket
if laddr == "" {
laddr = ":0"
}
var netladdr net.Addr
lerr := func(err error) error {
return &net.OpError{Op: "listen", Net: h.Network(), Addr: netladdr, Err: err}
}
host, port, err := h.resolveAddr(laddr)
if err != nil {
return nil, lerr(err)
}
netladdr = &Addr{Net: h.Network(), Host: host.name, Port: port}
if host != h {
return nil, lerr(errAddrNoListen)
}
// find first free port if autobind requested
if port == 0 {
sk = h.allocFreeSocket()
// else allocate socket in-place
} else {
// grow if needed
for port >= len(h.socketv) {
h.socketv = append(h.socketv, nil)
}
if h.socketv[port] != nil {
return nil, lerr(errAddrAlreadyUsed)
}
sk = &socket{host: h, port: port}
h.socketv[port] = sk
}
// create listener under socket
l := &listener{
socket: sk,
dialq: make(chan dialReq),
down: make(chan struct{}),
}
sk.listener = l
return l, nil
}
// Close closes the listener
// it interrupts all currently in-flight calls to Accept
func (l *listener) Close() error {
l.closeOnce.Do(func() {
close(l.down)
sk := l.socket
h := sk.host
n := h.network
n.mu.Lock()
defer n.mu.Unlock()
sk.listener = nil
if sk.empty() {
h.socketv[sk.port] = nil
}
})
return nil
}
// Accept tries to connect to Dial called with addr corresponding to our listener
func (l *listener) Accept() (net.Conn, error) {
h := l.socket.host
n := h.network
select {
case <-l.down:
return nil, &net.OpError{Op: "accept", Net: h.Network(), Addr: l.Addr(), Err: errNetClosed}
case req := <-l.dialq:
// someone dialed us - let's connect
pc, ps := net.Pipe()
// allocate sockets and register conns to Network under them
n.mu.Lock()
skc := req.from.allocFreeSocket()
sks := h.allocFreeSocket()
skc.conn = &conn{socket: skc, peersk: sks, Conn: pc}
sks.conn = &conn{socket: sks, peersk: skc, Conn: ps}
n.mu.Unlock()
req.resp <- skc.conn
return sks.conn, nil
}
}
// Dial dials address on the network
//
// It tries to connect to Accept called on listener corresponding to addr.
func (h *Host) Dial(ctx context.Context, addr string) (net.Conn, error) {
var netaddr net.Addr
derr := func(err error) error {
return &net.OpError{Op: "dial", Net: h.Network(), Addr: netaddr, Err: err}
}
n := h.network
n.mu.Lock()
host, port, err := h.resolveAddr(addr)
if err != nil {
n.mu.Unlock()
return nil, derr(err)
}
netaddr = &Addr{Net: h.Network(), Host: host.name, Port: port}
if port >= len(host.socketv) {
n.mu.Unlock()
return nil, derr(errConnRefused)
}
sks := host.socketv[port]
if sks == nil || sks.listener == nil {
n.mu.Unlock()
return nil, derr(errConnRefused)
}
l := sks.listener
// NOTE Accept is locking n.mu -> we must release n.mu before sending dial request
n.mu.Unlock()
resp := make(chan net.Conn)
select {
case <-ctx.Done():
return nil, derr(ctx.Err())
case <-l.down:
return nil, derr(errConnRefused)
case l.dialq <- dialReq{from: h, resp: resp}:
return <-resp, nil
}
}
// Close closes pipe endpoint and unregisters conn from Network
// All currently in-flight blocked IO is interrupted with an error
func (c *conn) Close() (err error) {
c.closeOnce.Do(func() {
err = c.Conn.Close()
sk := c.socket
h := sk.host
n := h.network
n.mu.Lock()
defer n.mu.Unlock()
sk.conn = nil
if sk.empty() {
h.socketv[sk.port] = nil
}
})
return err
}
// LocalAddr returns address of local end of connection
func (c *conn) LocalAddr() net.Addr {
return c.socket.addr()
}
// RemoteAddr returns address of remote end of connection
func (c *conn) RemoteAddr() net.Addr {
return c.peersk.addr()
}
// ----------------------------------------
// allocFreeSocket finds first free port and allocates socket entry for it.
// must be called with Network.mu held
func (h *Host) allocFreeSocket() *socket {
// find first free port
port := 1 // never allocate port 0 - it is used for autobind on listen only
for ; port < len(h.socketv); port++ {
if h.socketv[port] == nil {
break
}
}
// if all busy it exits with port >= len(h.socketv)
// grow if needed
for port >= len(h.socketv) {
h.socketv = append(h.socketv, nil)
}
sk := &socket{host: h, port: port}
h.socketv[port] = sk
return sk
}
// empty checks whether socket's both conn and listener are all nil
func (sk *socket) empty() bool {
return sk.conn == nil && sk.listener == nil
}
// addr returns address corresponding to socket
func (sk *socket) addr() *Addr {
h := sk.host
return &Addr{Net: h.Network(), Host: h.name, Port: sk.port}
}
func (a *Addr) Network() string { return a.Net }
func (a *Addr) String() string { return net.JoinHostPort(a.Host, strconv.Itoa(a.Port)) }
// ParseAddr parses addr into pipenet address
func (n *Network) ParseAddr(addr string) (*Addr, error) {
host, portstr, err := net.SplitHostPort(addr)
if err != nil {
return nil, err
}
port, err := strconv.Atoi(portstr)
if err != nil || port < 0 {
return nil, &net.AddrError{Err: "invalid port", Addr: addr}
}
return &Addr{Net: n.Network(), Host: host, Port: port}, nil
}
// Addr returns address where listener is accepting incoming connections
func (l *listener) Addr() net.Addr {
return l.socket.addr()
}
// Network returns full network name of this network
func (n *Network) Network() string { return NetPrefix + n.name }
// Network returns full network name of underlying network
func (h *Host) Network() string { return h.network.Network() }
// Copyright (C) 2017 Nexedi SA and Contributors.
// Kirill Smelkov <kirr@nexedi.com>
//
// This program is free software: you can Use, Study, Modify and Redistribute
// it under the terms of the GNU General Public License version 3, or (at your
// option) any later version, as published by the Free Software Foundation.
//
// You can also Link and Combine this program with other software covered by
// the terms of any of the Free Software licenses or any of the Open Source
// Initiative approved licenses and Convey the resulting work. Corresponding
// source of such a combination shall include the source code for all other
// software used.
//
// This program is distributed WITHOUT ANY WARRANTY; without even the implied
// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
//
// See COPYING file for full licensing terms.
// See https://www.nexedi.com/licensing for rationale and options.
package pipenet
import (
"context"
"fmt"
"io"
"net"
"reflect"
"testing"
"lab.nexedi.com/kirr/neo/go/xcommon/xsync"
"lab.nexedi.com/kirr/go123/exc"
)
// we assume net.Pipe works ok; here we only test Listen/Accept/Dial routing
// XXX tests are ugly, non-robust and small coverage
type mklistener interface {
Listen(string) (net.Listener, error)
}
func xlisten(n mklistener, laddr string) net.Listener {
l, err := n.Listen(laddr)
exc.Raiseif(err)
return l
}
func xaccept(l net.Listener) net.Conn {
c, err := l.Accept()
exc.Raiseif(err)
return c
}
type dialer interface {
Dial(context.Context, string) (net.Conn, error)
}
func xdial(n dialer, addr string) net.Conn {
c, err := n.Dial(context.Background(), addr)
exc.Raiseif(err)
return c
}
func xread(r io.Reader) string {
buf := make([]byte, 4096)
n, err := r.Read(buf)
exc.Raiseif(err)
return string(buf[:n])
}
func xwrite(w io.Writer, data string) {
_, err := w.Write([]byte(data))
exc.Raiseif(err)
}
func xwait(w interface { Wait() error }) {
err := w.Wait()
exc.Raiseif(err)
}
func assertEq(t *testing.T, a, b interface{}) {
t.Helper()
if !reflect.DeepEqual(a, b) {
fmt.Printf("not equal:\nhave: %v\nwant: %v\n", a, b)
t.Errorf("not equal:\nhave: %v\nwant: %v", a, b)
exc.Raise(0)
}
}
func TestPipeNet(t *testing.T) {
pnet := New("t")
xaddr := func(addr string) *Addr {
a, err := pnet.ParseAddr(addr)
exc.Raiseif(err)
return a
}
:= pnet.Host("α")
:= pnet.Host("β")
_, err := .Dial(context.Background(), ":0")
assertEq(t, err, &net.OpError{Op: "dial", Net: "pipet", Addr: xaddr("α:0"), Err: errConnRefused})
l1 := xlisten(, "")
assertEq(t, l1.Addr(), xaddr("α:1"))
// zero port always stays unused even after autobind
_, err = .Dial(context.Background(), ":0")
assertEq(t, err, &net.OpError{Op: "dial", Net: "pipet", Addr: xaddr("α:0"), Err: errConnRefused})
wg := &xsync.WorkGroup{}
wg.Gox(func() {
c1s := xaccept(l1)
assertEq(t, c1s.LocalAddr(), xaddr("α:2"))
assertEq(t, c1s.RemoteAddr(), xaddr("β:1"))
assertEq(t, xread(c1s), "ping")
xwrite(c1s, "pong")
c2s := xaccept(l1)
assertEq(t, c2s.LocalAddr(), xaddr("α:3"))
assertEq(t, c2s.RemoteAddr(), xaddr("β:2"))
assertEq(t, xread(c2s), "hello")
xwrite(c2s, "world")
})
c1c := xdial(, "α:1")
assertEq(t, c1c.LocalAddr(), xaddr("β:1"))
assertEq(t, c1c.RemoteAddr(), xaddr("α:2"))
xwrite(c1c, "ping")
assertEq(t, xread(c1c), "pong")
c2c := xdial(, "α:1")
assertEq(t, c2c.LocalAddr(), xaddr("β:2"))
assertEq(t, c2c.RemoteAddr(), xaddr("α:3"))
xwrite(c2c, "hello")
assertEq(t, xread(c2c), "world")
xwait(wg)
l2 := xlisten(, ":0") // autobind again
assertEq(t, l2.Addr(), xaddr("α:4"))
}
// Copyright (C) 2017 Nexedi SA and Contributors.
// Kirill Smelkov <kirr@nexedi.com>
//
// This program is free software: you can Use, Study, Modify and Redistribute
// it under the terms of the GNU General Public License version 3, or (at your
// option) any later version, as published by the Free Software Foundation.
//
// You can also Link and Combine this program with other software covered by
// the terms of any of the Free Software licenses or any of the Open Source
// Initiative approved licenses and Convey the resulting work. Corresponding
// source of such a combination shall include the source code for all other
// software used.
//
// This program is distributed WITHOUT ANY WARRANTY; without even the implied
// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
//
// See COPYING file for full licensing terms.
// See https://www.nexedi.com/licensing for rationale and options.
package xnet
// network tracing
import (
"context"
"net"
)
// NetTrace wraps underlying networker with IO tracing layer
//
// Tracing is done via calling trace func right after corresponding networking
// event happenned. No synchronization for notification is performed - if one
// is required tracing func must implement such synchronization itself.
//
// only initiation events are traced:
//
// 1. Tx only (no Rx):
// - because Write, contrary to Read, never writes partial data on non-error
// - because in case of pipenet tracing writes only is enough to get whole network exchange picture
//
// 2. Dial only (no Accept)
// - for similar reasons.
//
// WARNING NetTrace functionality is currently very draft.
func NetTrace(inner Networker, tracer Tracer) Networker {
return &netTrace{inner, tracer}
}
// Tracer is the interface that needs to be implemented by network trace receivers
type Tracer interface {
TraceNetConnect(*TraceConnect)
TraceNetListen(*TraceListen)
TraceNetTx(*TraceTx)
}
// TraceConnect is event corresponding to network connection
type TraceConnect struct {
// XXX also put networker?
Src, Dst net.Addr
Dialed string
}
// TraceListen is event corresponding to network listening
type TraceListen struct {
// XXX also put networker?
Laddr net.Addr
}
// TraceTx is event corresponding to network transmission
type TraceTx struct {
// XXX also put network somehow?
Src, Dst net.Addr
Pkt []byte
}
// netTrace wraps underlying Networker such that whenever a connection is created
// it is wrapped with traceConn.
type netTrace struct {
inner Networker
tracer Tracer
}
func (nt *netTrace) Network() string {
return nt.inner.Network() // XXX + "+trace" ?
}
func (nt *netTrace) Dial(ctx context.Context, addr string) (net.Conn, error) {
// XXX +TraceNetDialPost ?
c, err := nt.inner.Dial(ctx, addr)
if err != nil {
return nil, err
}
nt.tracer.TraceNetConnect(&TraceConnect{Src: c.LocalAddr(), Dst: c.RemoteAddr(), Dialed: addr})
return &traceConn{nt, c}, nil
}
func (nt *netTrace) Listen(laddr string) (net.Listener, error) {
// XXX +TraceNetListenPre ?
l, err := nt.inner.Listen(laddr)
if err != nil {
return nil, err
}
nt.tracer.TraceNetListen(&TraceListen{Laddr: l.Addr()})
return &netTraceListener{nt, l}, nil
}
// netTraceListener wraps net.Listener to wrap accepted connections with traceConn
type netTraceListener struct {
nt *netTrace
net.Listener
}
func (ntl *netTraceListener) Accept() (net.Conn, error) {
c, err := ntl.Listener.Accept()
if err != nil {
return nil, err
}
return &traceConn{ntl.nt, c}, nil
}
// traceConn wraps net.Conn and notifies tracer on Writes
type traceConn struct {
nt *netTrace
net.Conn
}
func (tc *traceConn) Write(b []byte) (int, error) {
// XXX +TraceNetTxPre ?
n, err := tc.Conn.Write(b)
if err == nil {
tc.nt.tracer.TraceNetTx(&TraceTx{Src: tc.LocalAddr(), Dst: tc.RemoteAddr(), Pkt: b})
}
return n, err
}
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